LibTiff Mailing List
TIFF and LibTiff Mailing List Archive
January 2007
Previous Thread
Next Thread
Previous by Thread
Next by Thread
Previous by Date
Next by Date
Contact
The TIFF Mailing List Homepage
This list is run by Frank Warmerdam
Archive maintained by AWare Systems
Thread
2007.02.01 18:34 "Re: Interpreting SubIFDs tag", by Joris Van Damme
Phil, Phil Harvey wrote: > > Here is the document that invented the SubIFD concept -- this is the > > "Tiff Trees" approach. > > (http://partners.adobe.com/public/developer/en/tiff/TIFFPM6.pdf) > > To quote this specification: > > "If there is more than 1 child image for a given parent image, the > NextIFD value of Child #1 must point to Child #2, and so on. The last > Child’s NextIFD value must be zero." > > I should point out that Adobe themselves don't store multiple > SubIFD's like this. > > The current version of the Adobe DNG converter writes multiple > SubIFD's by storing a separate pointer for each in the SubIFD tag > (and each SubIFD has a zero NextIFD pointer). > > But this is definitely not the first time that Adobe has ignored > their own specification. I don't think they ignored their own specification... A subpart of a spec, is never able to overwrite the grand scheme. The grand scheme does any tag to be an array of values. Best regards, Joris Van Damme info@awaresystems.be http://www.awaresystems.be/ Download your free TIFF tag viewer for windows here: http://www.awaresystems.be/imaging/tiff/astifftagviewer.html